Such combing machines are used to remove natural impurities contained in cotton fibers or wool fibers and to align the fibers of the sliver or group of fibers parallel to each other. To accomplish this, a prepared sliver is clamped between the jaws of the gripper arrangement in such a way that a certain portion of the length of the fibers extends beyond the front of the jaws in the form of a so-called tuft. This tuft is combed and thus cleaned by means of the comb segment, equipped with a set of needles or teeth, of the combing roller. The draw-off device as a rule consists of two oppositely rotating rollers which grip the combed tuft and move it on.
So as to be able to draw the partially cleaned fibers with the rollers of the draw-off device out of the jaws of the gripper unit, either the comparatively heavy draw-off device must move linearly or in the form of a section of a circle in relation to the tuft held between the jaws of the gripper device or, in the reverse way, the gripper device must be moved towards the stationary draw-off rollers. See, for example, German published patent application DE-05 28 45 245. With 200 to 350 comb movements per minute usually required, and in view of the great masses to be moved, this results in a great amount of dynamic agitation of the entire combing machine and limits its working speed.
In conventional combing machines there is the additional problem that when the combed fibers are drawn off by the counter-rotating draw-off rollers, up to 50% of the fiber length has not been cleaned by the circular comb because it was clamped between the jaws of the gripper device during the combing process. In order to also clean this portion of the fibers as thoroughly as possible, in the conventional way these fibers are drawn through a fixed comb disposed ahead of the draw-off rollers. Such a fixed comb, consisting of one or at best two rows of needles, naturally does not have the cleaning effect of a comb segment covered with thousands of tips.